MANAMA, Bahrain: Riot police and mourners have clashed in Bahrain following the funeral of an 8-year-old boy whom opposition groups claim died from respiratory problems triggered by heavy tear gas.

Officials did not immediately comment on the cause of the boy's death after he was hospitalized Jan. 19.

Rights groups and others have complained about intense tear gas use by Bahraini forces during nearly two years of unrest.

Hundreds of mourners staged a protest march following Sunday's burial, but were dispersed by riot police firing tear gas and stun grenades. Some protesters hurled firebombs.

Bahrain has been wracked by conflict between the Sunni-led monarchy and majority Shiites seeking a greater political voice.

More than 55 people have died in the unrest in the strategic kingdom, home to the U.S. Navy's 5th Fleet.